Put that CSS down.

NOW!

I'm Lucas, aka Vilaboim

Front End Developer

and VITTANO

Front End Developer

vilaboim.com

github.com/vilaboim

facebook.com/luvilaboim

linkedin.com/in/vilaboim

Preprocessors

What?

Why?

Features

Selectors

body
    color white

textarea
input
    border 1px solid #eee

.header
    .menu
        background-color red

Stylus

body {
    color: #fff;
}

textarea,
input {
    border: 1px solid #eee;
}

.header .menu {
    background-color: #f00;
}

CSS

Parent Reference

.btn
a.btn
    color #a7a7a7

    &:hover
        color #000

    > span
        font-size 10px

Stylus

textarea,
input {
    color: #a7a7a7;
}

textarea:hover,
input:hover {
    color: #000;
}

CSS

Parent Reference

.menu
    border 2px #f00 solid

    .home &
        border 2px #000 solid

Stylus

.menu {
    border: 2px #f00 solid;
}

.home .menu {
    border: 2px #000 solid;
}

CSS

Partial Reference

.list
    list-style none

    &__item
        text-decoration underline

Stylus

.list {
    list-style: none;
}

.list__item {
    text-decoration: underline;
}

CSS

Variables

font-size     = 1.4em
font          = font-size "Open Sans", Arial
primary-color = #ccc


body
  font  font, sans-serif
  color primary-color

Stylus

body {
    font: 1.4em "Open Sans", Arial, sans-serif;
    color: #ccc;
}

CSS

Property Lookup

.logo
    position    absolute
    top         50%
    left        50%
    width       w = 150px
    height      h = 80px
    margin-left -(w / 2)
    margin-top  -(h / 2)

Using Variables

.logo
    position    absolute
    top         50%
    left        50%
    width       150px
    height      80px
    margin-left -(@width / 2)
    margin-top  -(@height / 2)

Using Property Lookup

Conditional properties

position()
    z-index  1 unless @z-index
    position arguments

.header
    z-index  20
    position(absolute)

.header-home
    position(absolute)

Stylus

.header {
    z-index: 20;
    position: absolute;
}

.header-home {
    z-index: 1;
    position: absolute;
}

CSS

Mixins

flex()
    display -ms-flexbox
    display -webkit-flex
    display flex

.container
    flex()

Stylus

.container {
    display: -ms-flexbox;
    display: -webkit-flex;
    display: flex;
}

CSS

Block Mixins

placeholder(element)
    {element}::-webkit-input-placeholder
        {block}

    {element}::-moz-placeholder
        {block}

    {element}:-ms-input-placeholder
        {block}

    {element}:-moz-placeholder
        {block}

+placeholder(input)
    color      #ccc
    font-style italic

Stylus

input::-webkit-input-placeholder {
    color: #ccc;
    font-style: italic;
}

input::-moz-placeholder {
    color: #ccc;
    font-style: italic;
}

input:-ms-input-placeholder {
    color: #ccc;
    font-style: italic;
}

input:-moz-placeholder {
    color: #ccc;
    font-style: italic;
}

CSS

Mixins in Mixins

listItem()
    text-decoration underline

list()
    list-style none

    > li
        listItem()

ul
    list()

Stylus

ul {
    list-style: none;
}

ul > li {
    text-decoration: underline;
}

CSS

Functions

grid-col(n)
    ( 100% / 12 ) * n

.sidebar
    width grid-col(3)

.article
    width grid-col(9)

Stylus

.sidebar {
    width: 25%;
}

.article {
    width: 75%;
}

CSS

Function Bodies

inner-rad(b, p)
    b = unit(b, px)
    p = unit(p, px)
    b - p

.button
    padding       15px
    border-radius 20px

    .button-inner
        border-radius inner-rad(@border-radius, 15px)

Stylus

.button {
    padding: 15px;
    border-radius: 20px;
}

.button .button-inner {
    border-radius: 5px;
}

CSS

Multiple Return Values

padd(width, height)
    width / 10 height / 10

.container
    width   150px
    height  100px
    padding padd(@width, @height)

Stylus

.container {
    width: 150px;
    height: 100px;
    padding: 15px 10px;
}

CSS

Conditionals

black-friday = false

body
    if black-friday is true
        color      white
        background black
    else
        color      black
        background white
black-friday = true

body
    if black-friday is true
        color      white
        background black
    else
        color      black
        background white
body {
    color: #000;
    background: #fff;
}

Stylus

body {
    color: #fff;
    background: #000;
}

CSS

CSS

Stylus

With Mixins

flex-justify(val)
    -webkit-justify-content val
    justify-content         val

    if val is 'space-around'
        -ms-flex-pack distribute
    else if val is 'flex-end'
        -ms-flex-pack end
    else if val is 'space-between'
        -ms-flex-pack justify
    else
        -ms-flex-pack val

.banners
    flex-justify(space-around)

.container
    flex-justify(space-between)

.footer
    flex-justify(center)

Stylus

.banners {
    -webkit-justify-content: space-around;
    justify-content: space-around;
    -ms-flex-pack: distribute;
}

.container {
    -webkit-justify-content: space-between;
    justify-content: space-between;
    -ms-flex-pack: justify;
}

.footer {
    -webkit-justify-content: center;
    justify-content: center;
    -ms-flex-pack: center;
}

CSS

Built-in Functions

/* Darken */
.sidebar
    background-color darken(red, 10%)

/* Lighten */
.container
    background-color lighten(blue, 80%)

/* RGBA */
.footer
    background-color rgba(white, .5)

Stylus

/* Darken */
.sidebar {
    background-color: #e60000;
}

/* Lighten */
.container {
    background-color: #ccf;
}

/* RGBA */
.footer {
    background-color: rgba(255,255,255,0.5);
}

CSS

Range

for i in range(0px, 50px, 5)
    .p-t-{i}
        padding-top: i

Stylus

.p-t-0 {
    padding-top: 0px;
}

.p-t-5 {
    padding-top: 5px;
}

.p-t-10 {
    padding-top: 10px;
}

.p-t-15 {
    padding-top: 15px;
}

...

CSS

Prefix Classes

+prefix-classes('col-')
    .xs-1
    .xs-2
    .xs-3
    .xs-4
    .xs-5
    .xs-6
    .xs-7
    .xs-8
    .xs-9
    .xs-10
    .xs-11
    .xs-12
        display inline-block

Stylus

.col-xs-1,
.col-xs-2,
.col-xs-3,
.col-xs-4,
.col-xs-5,
.col-xs-6,
.col-xs-7,
.col-xs-8,
.col-xs-9,
.col-xs-10,
.col-xs-11,
.col-xs-12 {
    display: inline-block;
}

CSS

Iteration

+prefix-classes('col-')
    for num in 1..12
        .xs-{num}
        .md-{num}
        .sm-{num}
        .lg-{num}
            width ( 100% / 12 ) * num

Stylus

.col-xs-1,
.col-md-1,
.col-sm-1,
.col-lg-1 {
    width: 8.333333333333334%;
}

.col-xs-2,
.col-md-2,
.col-sm-2,
.col-lg-2 {
    width: 16.666666666666668%;
}

...

CSS

With mixins

flex-basis(val)
    -moz-flex-basis    val
    -webkit-flex-basis val
    flex-basis         val

for num in 1..12
    .col-xs-{num}
        flex-basis(( 100% / 12 ) * num)

Stylus

.col-xs-1 {
    -moz-flex-basis: 8.333333333333334%;
    -webkit-flex-basis: 8.333333333333334%;
    flex-basis: 8.333333333333334%;
}

.col-xs-2 {
    -moz-flex-basis: 16.666666666666668%;
    -webkit-flex-basis: 16.666666666666668%;
    flex-basis: 16.666666666666668%;
}

.col-xs-3 {
    -moz-flex-basis: 25%;
    -webkit-flex-basis: 25%;
    flex-basis: 25%;
}

...

CSS

With Mixins (again)

icon-classes = fb-icon insta-icon twitter-icon

icons(className)
    li.{className}
        background-image url(className'.png')

ul.icons
    for num in 0..length(icon-classes) - 1
        icons(icon-classes[num])

Stylus

ul.icons li.fb-icon {
    background-image: url("fb-icon.png");
}

ul.icons li.insta-icon {
    background-image: url("insta-icon.png");
}

ul.icons li.twitter-icon {
    background-image: url("twitter-icon.png");
}

CSS

Extend

.alert
    display          inline-block
    border-radius    3px
    padding          5px
    color            #fff
    background-color blue

.alert-success
    @extend          .alert
    background-color green

.alert-danger
    @extend          .alert
    color            #fff
    background-color red

Stylus

.alert,
.alert-success,
.alert-danger {
    display: inline-block;
    border-radius: 3px;
    padding: 5px;
    color: #fff;
    background-color: #00f;
}

.alert-success {
    background-color: #008000;
}

.alert-danger {
    color: #fff;
    background-color: #f00;
}

CSS

Import and Require

/* IMPORT */

@import mixins

@require functions

Stylus

/* IMPORT */

body {
    font: 1.4em "Open Sans", Arial, sans-serif;
    color: #ccc;
}

.logo {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 150px;
    height: 80px;
    margin-left: -75px;
    margin-top: -40px;
}

...

CSS

Thank you!